Warmup

1
Warm-up!

• Write the balanced equation and identify the
  reaction type.
• Sodium sulfide reacts with silver nitrate to
  produce silver sulfide and sodium nitrate.
• Mercury(II) oxide upon heating yields liquid
  mercury and oxygen gas.
• Octane (C8H18) burns with oxygen to produce
  carbon dioxide and water.

2
How did you do?

• synthesis
• decomposition
• single replacement
• double replacement
• combustion

3
Synthesis

• A Y ? AY
• Two or more substances combine to form one

4
Decomposition

• AY ? A Y
• One substance breaks down into two or more
  simpler substances

5
Single Replacement

• A BY ?B AY
• One element replaces another element in a compound

6
Double Replacement

• AY BZ ?AZ BY
• Two compounds exchange parts to become two new
  compounds

7
Combustion

• CxHy O2 ? CO2 H2O
• A hydrocarbon burns in oxygen, forming carbon
  dioxide and water.

8
Sodium sulfide reacts with silver nitrate to
produce silver sulfide and sodium nitrate.

• Type?
• Double replacement
• Review nomenclature? You must know it!
• Na S-2 Ag NO3- ? Ag S-2 Na NO3-
• Na2S AgNO3 ? Ag2S NaNO3
• Na2S 2AgNO3 ? Ag2S 2NaNO3

9
Mercury(II) oxide upon heating yields liquid
mercury and oxygen gas.

• Type?
• Decomposition
• Hg2O-2 ? Hg (l) (Brinclhof!) O2(g)
• HgO ? Hg (l) O2(g)
• 2HgO ? 2Hg (l) O2(g)

10
Octane (C8H18) burns with oxygen to produce
carbon dioxide and water.

• Combustion
• C8H18 O2 ? CO2 H2O
• 2C8H18 25 O2 ? 16CO2 18H2O
• From now on, we will assume you have these
  skills. If not, come in for
  tutoring! ?

asap
11
Predicting Products

• Identify reaction type.
• Use nomenclature rules.
• Learn some simple patterns.

12
Synthesis

• Must be told products for many synthesis
  reactions, but there are a few
  you can learn.

patterns
13
Synthesis 2 elements?compound

• Hydrogen chlorine ? ?
• Hydrogen chloride (hydrochloric acid)
• H2 Cl2 ? HCl (balanced?)
• Potassium iodine ? ?
• Potassium iodide
• K I2 ? KI (balanced?)

14
Decomposition

• Opposite of the synthesis ones.
• Binary compound?two elements

15
Try these decomposition reactions!

• Molten table salt is electrolyzed.
• NaCl(l) ?Na Cl2 (balanced?)
• Phosphorus trioxide is decomposed.
• PO3 ? P O2 (balanced?)

16
Single Replacement Prediction

• One metal replaces another metal only if it is
  more reactive than the first metal.
• Activity Series (back of periodic table) helps
  predict.
• Higher on list more reactive (gets to be in
  compound)
• Lower on list less reactive (must be alone)

17
Single Replacement

• Copper metal magnesium chloride??
• Will copper replace magnesium?
• No! It is lower on activity series!
• Magnesium copper(II) chloride --?
• Will magnesium replace copper?
• Yes! It is higher on activity series!
• Mg CuCl2 ??
• Mg CuCl2 ? MgCl2 Cu

18
More SR Prediction

• Zinc metal is placed in copper(II) nitrate.
• Zn Cu(NO3)2 ??
• Zn gt Cu (higher than Cu)
• Zn Cu(NO3)2 ? Zn(NO3)2 Cu
• Silver metal is placed in copper(II) bromide.
• Ag CuBr2--?
• Ag lt Cu so?
• No reaction (NR)! ?

19
SR with Halogens

• Activity series for halogens is same as column
  on periodic table.
• F2gtCl2gtBr2gtI2
• Sodium fluoride chlorine?
• NaF Cl2--?
• NR
• Sodium chloride fluorine?
• NaCl F2 ?NaF Cl2

20
Double Replacement

• Will occur if at least one of the products is
• Gas
• Solid (precipitate) (see solubility rules)
• Covalent compound (water, for example)
• (For now we assume they all work!)
• Trade cations or anions. Be sure you dont have
  two of the same type together. (No two metals,
  for ex.)

21
DR Practice

• Barium fluoride potassium hydroxide??
• BaF2 KOH ??
• BaF2 KOH ?Ba(OH)2 KF
• (Dont forget to balance at the end!)
• Hydrochoric acid sodium hydroxide??
• HCl NaOH??
• HCl NaOH?HOH NaCl
• HCl NaOH?H2O NaCl

22
Identifying Precipitates

• See solubility rules on back of PT.
• If its insoluble, it is a ppt on product side.
  Label it (s).
• Ex Barium sulfate
• Rule Sulfate Ba2
• Not Soluble
• BaSO4 (s)

23

• Ex Silver chloride
• Rule Chloride Ag
• Not Soluble
• AgCl (s)
• Ex Sodium hydroxide
• Rule Hydroxide Group 1A ions or ammonium
• Soluble! Does not ppt!
• NaOH (aq)